Effect of 35% hydrogen peroxide in promoting enamel whitening with orthodontic attachments bonded on its surface

Although teeth whitening is preferred after orthodontic treatment, aesthetic demands may generate a different indication. Aim: To determine the factors associated with indication of tooth whitening during orthodontic treatment. A cross-sectional study was conducted using an online survey for participation of 200 dentists who frequently performed fixed orthodontic treatment. The validity and reliability of a 10 questions instrument was determined, content was entered into Survey Monkey software to generate delivery links. The instrument was sent through social networks with instant messaging and email. The bivariate analysis of associated factors was evaluated with Chi Square test and logistic regression was used to identify risk or protective factors for indication of tooth whitening. In bivariate analysis, it was found that dentist's specialization in orthodontics (p-value = 0.006), intensity of patient's tooth staining (p-value = 0.001), patient's staining habits (p-value = 0.001) and patient's self-perceived aesthetic need (p-value = 0.001) were associated with indication of tooth whitening during orthodontic treatment. While professional experience (p-value = 0.525) and training in dental aesthetics (p-value = 0.936) were not associated. In adjusted analysis, differences were found between those who are specialists in orthodontics versus those who are not (p-value = 0.035), multiplying by 2.750 their decision to indicate tooth whitening (OR=2.750). The decision to indicate tooth whitening during orthodontic treatment is low. However, this initial decision could be affected by intensity of tooth staining, pigmentation habits and patient's self-perceived need for dental aesthetics; but mainly by orthodontics specialization of dentist. Key words:Tooth bleaching, fixed orthodontic appliance, brackets, dentists.

The aim of this study was to evaluate effect of adding sodium fluoride (NaF) to the in-office bleaching gel on bleaching sensitivity (BS) and tooth whitening. Two maxillary quadrants from 32 patients were randomly allocated to intervention and control groups in a split-mouth design. In control group, bleaching gel containing 40% hydrogen peroxide and in intervention group, the same gel with 2% NaF were applied for 45min. Before treatment, immediately, 24h, 7d, 30d and 90d after treatment, sensitivity to cold, touch and spontaneous stimuli was measured through Visual Analogue Scale (VAS). Color changes were evaluated by a spectrophotometer and reported through ΔE and ΔSGU values. Data were analyzed by Shapiro-Wilk, 2Q AZMann-Whiteny U, Friedman and Wilcoxon tests (α = 0.05). A total of 29 patients completed the study. The cold and spontaneous sensitivity significantly decreased from baseline until 90d post-bleaching in both groups (P < 0.001), while a significant decline in tactile sensitivity demonstrated only in NaF group (p = 0.01). In the comparison between two groups, only the cold sensitivity was significantly lower in NaF group at 90d after bleaching (p = 0.040). There was no significant difference between two groups in ΔE/ΔSGU values at any of evaluation intervals. The incorporation of 2% NaF into the bleaching gel significantly reduced cold sensitivity after 90d, with no detrimental effects on whitening effectiveness. (IRCT20200906048639N1) CLINICAL RELEVANCE: The in-office bleaching gel containing 2% NaF did not demonstrate a beneficial impact on BS. Nonetheless, it did not negatively affect the results of tooth whitening.

Click to increase image sizeClick to decrease image sizeKeywords: BLEACHING AGENTRESTORATIVE MATERIALSMICROHARDNESS

Introduction: Tooth whitening (Bleaching) is a method to restore discoloured teeth to the original tooth colour with a chemical process. The materials used in the bleaching process are hydrogen peroxide, sodium perborates and carbamide peroxide. Pear fruit consists of hydrogen peroxide which is potentially an oxidizing compound that produces free radicals that react with unsaturated bonding teeth staining substances. This study aims to analyzed tooth whitening effect of exposure of pear juice with different frequencies. Methods: The type of research was true in vitro experiment where samples of 32 maxillary premolar teeth had cut the root to CEJ. The specimens divided into four groups. The first group was soaked in pear juice two times, the second group three times, a third group four times, and the fourth was the control group using only mineral water. Tooth colour was measure using a Spectrophometer, conducted before and after individual soaking. Results: The research result is tested with ANOVA and Newman- Keuls Range Test showed a significant difference of tooth whitening degree between the frequency exposure pear juice after 2 times soaking, 3 times soaking and 4 times soaking. Conclusion: There are difference degree of whitening from the difference frequency exposure of pear juice and Pear juice exposure of 4 times gives higher whitening effect compared to frequency of 3 times, 2 times and control group which is soaked in water.

Hypothesis Testing

Introduction Tooth color is a key factor in the perception of an attractive smile, making bleaching a widely sought-after cosmetic dental procedure. Valued for its minimally invasive approach, this technique effectively lightens teeth to achieve desired aesthetic outcomes. As the desire for immediate results grows among patients, various bleaching agents, and energy sources have been developed to expedite the bleaching process. The study aims to evaluate and compare the efficacy of 35% hydrogen peroxide activated by light-emitting diode (LED) and laser on artificially stained teeth, assessing color changes at different time intervals. Methodology Sixty maxillary central incisors with intact crowns were selected for the study. An artificial staining solution was prepared, and the samples were immersed in it for 15 days to simulate staining. After this period, the teeth were removed from the solution, rinsed with water, and dried. Baseline photographs of each tooth were taken for comparison. The teeth were then divided into two groups, one treated with LED activation and the other with laser activation of 35% hydrogen peroxide as the bleaching agent. The color changes were measured and recorded at different time intervals. Data were presented as mean and standard deviation, with statistical analysis conducted using independent sample t-test and repeated measures ANOVA to compare the efficacy of the two methods. Results Both LED and laser activation of 35% hydrogen peroxide demonstrated significant color changes in the stained teeth. The initial color improvement was noticeable in both groups, with LED and laser treatments producing comparable whitening effects. The mean color change values indicated that both activation sources were effective in enhancing the bleaching process, providing immediate and substantial results. Statistical analysis showed no significant difference between the two methods, suggesting their equivalency in clinical efficacy for tooth bleaching. Conclusion The study concludes that both LED and laser activation of 35% hydrogen peroxide are efficient methods for in-office tooth bleaching, providing immediate and enhanced whitening effects. The comparable results between the two energy sources indicate that can be effectively used to meet the increasing demand for rapid aesthetic improvements in a clinical setting. This finding supports the adoption of both LED and laser bleaching techniques as viable options for dental practitioners aiming to achieve optimal patient satisfaction with minimal invasiveness.

Effect of laser irradiation on crystalline structure of enamel surface during whitening treatment with hydrogen peroxide

BackgroundAt present, there are limited studies on how tooth whitening procedures are applied in orthodontic patients. Therefore, the objective of this study was to assess the perception of tooth whitening practices during and after orthodontic treatment. Material and MethodsA survey of orthodontists in Medellín (Colombia) between January and October 2020 was carried out. The survey instrument was developed to obtain information regarding the perception and practices of tooth whitening during and after orthodontic treatment. Results133 orthodontists with a mean age of 41,6 years old participated in the survey. Over 60% of participants reported >6 years of experience as orthodontist. The majority (99,2%) reported that their patients request tooth whitening. Of these, 71,2% refer the patient to another dental professional for the procedure while 28,8% administers it. More than half of orthodontists reported that their patients request dental whitening during orthodontic treatment. The majority (>90%) of orthodontists do not recommend tooth whitening during orthodontic treatment. Furthermore, >80% consider that tooth whitening is best recommended after brackets have been removed.ConclusionsRequests for tooth whitening from orthodontic patients is very frequent and most orthodontists favor the referral to another dental professional for the procedure. The majority do not recommend tooth whitening during orthodontic treatment and prefer waiting 1 to 3 months after brackets removal for the procedure. Key words:Tooth whitening, orthodontic treatment, brackets.

Currently dental aesthetics during fixed orthodontic treatment is an option required by patients, due to the frequent pigmentations that can occur in tooth enamel as a result of inadequate oral hygiene and plaque retention caused by fixed appliances. To determine the effectiveness of dental whitening and its side effects during active fixed orthodontic treatment, as an alternative aesthetic treatment in certain cases that merit it. This narrative review evaluated 35 scientific articles from the Medline information sources (via PUBMED), EMBASE, SCOPUS, SCIELO and LILACS from the last 10 years, published in Spanish, Portuguese and English. We included 17 articles that met the selection criteria which were randomized clinical trials and observational studies, in vitro studies and in vivo studies that evaluated in-office dental clearance, performed on patients using fixed orthodontic treatment at that time. Systematic reviews, case reports and editorials were excluded. It was observed that dental whitening in patients with active orthodontic treatment minimally affects the adhesion of the orthodontic apparatus to the tooth surface. In addition, some studies observed that the brackets interfere with the extension of the dental lightening, evidencing slightly darker areas. Dental whitening during orthodontic treatment can be given efficiently in clinical practice, depending on the aesthetic requirement of the patient. However, it is a recommended procedure in certain cases of great need for immediate aesthetics, since, the material with which the brackets are installed on the dental surface, will interfere with the extension of the lightening material, resulting in a darker shade in that sector and different from the surrounding tissue. Likewise, it will intervene in the adhesion to the dental surface, having many probabilities that the orthodontic apparatus can detach.

Total sodium replacement by calcium in trimetaphosphate and its incorporation into dental whitening gels: A novel strategy for in-office treatment.

Background: The tooth bleaching treatment can cause structural changes in the surfaces of the teeth; these changes can increase the absorption of staining agents. Purpose: This study assessed surface morphological changes and predisposition to staining in dental enamel bleached with different hydrogen peroxide (HP) concentrations, with or without the use of a light source (LS). Methods: 25 bovine incisor specimens were divided into five groups (n = 5): Control- no treatment; HP35 - hydrogen peroxide 35%; HP35+LED - hydrogen peroxide 35% + light emission; HP20 - hydrogen peroxide 20%; and HP7 - hydrogen peroxide 7,5%. Twenty days after bleaching, the specimens were immersed in staining solutions four hours a day for 28 days. The morphological alterations of the bovine enamel surface were evaluated by means of scanning electron microscopy, X-ray dispersive energy spectroscopy and predisposition to the staining of the brightened enamel by means of colorimetry. Results: ANOVA with Tukey's test (p&lt;0.05) showed that HP7 had the highest ΔL values (p=0.176) (brightest), with a better lightening effect. The bleached groups exhibited morphological changes in the enamel. The groups did not exhibit significant changes in oxygen, calcium, and phosphorus values (p=0.020). The presence or absence of light was not significant (p=0.007) for the predisposition to staining in bleached teeth. Conclusion: The time of exposure to the staining solution was significant for staining bovine dental enamel. High concentrations of HP were not necessary for achieving effective bleaching. HP caused an increase in enamel porosity and depressions. The light source did not influence bleaching.

Objectives: This study aimed to compare the efficiency of three different substances used for the bleaching of non-vital teeth. Methods: Forty bovine teeth were divided into five groups: three test groups (sodium perborate + 20% hydrogen peroxide – SPG; 37% carbamide peroxide – CPG; 35% hydrogen peroxide – HPG) and two control groups (CG1 and CG2). Teeth of the test groups were stained artificially with blood and bleached using the in-office and walking bleach techniques. The efficiency of the bleaching agents was evaluated objectively by comparing the color variables L*, a*, and b* measured spectrophotometrically according to the CIELab system. The data were analyzed by ANOVA and the Tukey test, adopting a 5% level of significance. Results: The results showed a reduction in lightness (L*) after staining and an increase after the bleaching sessions. The values of a* and b* increased after staining and decreased after the application of the bleaching substances. Conclusions: All substances used for non-vital tooth bleaching exhibited the same bleaching efficiency. No significant differences in this efficiency were observed between the bleaching techniques at the end of the experiment. However, in-office bleaching provided the same bleaching result as the walking bleach technique within a shorter period. Clinical significance: Given the increasing demand for esthetics, the use of different bleaching techniques and the variety of whitening agents, oral health professionals should offer evidence-based treatment, more efficient and in less time.

BackgroundTo investigate the effect of a 50% ascorbic acid with 50% citric acid solution on the immediate shear bond strength (SBS) of metallic brackets after tooth bleaching. The enamel etching pattern and the required quantity of these combined acids as antioxidants following 35% hydrogen peroxide (HP) bleaching were also determined.MethodsThe stability of the solution at room temperature was assessed at various time intervals. Fifty teeth were randomly divided into five groups: non-bleached (G1), bleached then acid etched (G2), bleached followed by a 10-minute treatment with 10% sodium ascorbate and acid etched (G3), 5-minute treatment with 50% ascorbic acid (G4), and 5-minute treatment with a combination of 50% ascorbic acid and 50% citric acid (G5). Groups G2, G3, G4 and G5 were bleached by 35% HP gel for a total of 32 min. Acid etching in groups G1, G2, and G3 was performed using 37% phosphoric acid (Ormco®, Orange, CA, USA) for 15 s. In all groups, metal brackets were immediately bonded using Transbond™ XT primer and Transbond™ PLUS adhesive, with light curing for 40 s. The SBS was tested with a universal testing machine, and statistical analysis was conducted using one-way ANOVA followed by Tukey’s HSD test. The level of significance was set at p < 0.05 for all statistical tests.ResultsStability tests demonstrated that the combined acids remained effective for up to 21 days. Group G5 significantly increased the SBS of bleached teeth to the level of G1 (p < 0.05), while G3 did not achieve the same increase in SBS (p > 0.05). SEM analysis revealed enamel etching patterns similar to those of both control groups (G1 and G2). Kinetic studies at 6 min indicated that the antioxidation in G5 reacted 0.2 mmole lower than in G3 and G4.Conclusion5-minute application of the combined acids enhanced the SBS of bleached teeth comparable to unbleached teeth. The combined acids remain stable over two weeks, presenting a time-efficient, single-step solution for antioxidant application and enamel etching in orthodontic bracket bonding.

To demonstrate that it is possible to pursue teeth whitening treatment protocols during orthodontic treatment with no esthetic loss. Many patients undergoing orthodontic treatment desire to have a straight and well aligned dentition, but also whiter teeth. For many years, it was believed that carrying out a whitening treatment with positioned orthodontic brackets in place would result in localized spots on the enamel labial surfaces of teeth. However, a deeper understanding of the bleaching process suggests that the oxidation caused by products, which results from hydrogen peroxide decomposition, are able to diffuse peripherally into the tooth structure and reach even that under the cemented brackets. Two in-office-bleaching treatments were performed in patients using orthodontic fixed braces in two or three 40-minute sessions using a 35% hydrogen peroxide. In-office bleaching is possible and effective, even with orthodontic brackets in position. The teeth were successfully bleached despite the presence of brackets. All biological criteria have been fulfilled satisfying patients' expectations of aligned and whitened teeth in less time than if treatments had been performed separately, with satisfactory results and no esthetic loss. The whitening of teeth is possible during orthodontic treatment with fixed braces without any esthetic loss. The in-office bleaching treatment with brackets in position also may act as a motivation factor, preventing patient withdrawal or treatment interruption. Therefore, at the end of the orthodontic treatment, the patient is able to display an aligned, functional and whitened smile. (J Esthet Restor Dent 29:83-92, 2017).

This systematic review aimed to identify and critically evaluate the available evidence of the appropriate moment to perform tooth whitening in conventional orthodontic patients. A systematic review in MEDLINE and SciELO databases from inception to February 2021 was carried out by two independent reviewers. Randomized clinical trials, non-randomized clinical trials, case-control, cohort, cross-sectional, case-series and reviews that focused on the application of tooth whitening during or after orthodontic treatment were considered for inclusion. The primary outcome was defined as tooth whitening during/after orthodontic treatment. The secondary outcome included the time in days after bracket debonding in which tooth whitening was performed. Risk of bias analysis was performed for each study and the findings were synthesized in a narrative summary. A total of 4 randomized clinical trials, 1 non-randomized clinical trial and 3 reviews were included in the qualitative synthesis. One study performed tooth whitening during, and three studies after orthodontic treatment. One study compared tooth whitening during and after orthodontic treatment. The time after which tooth whitening was applied following bracket debonding ranged from 7 to 90 days with a mean value of 40.2 days. All studies reported satisfactory improvements in tooth color shade during or after orthodontic treatment independent of the protocol. Low quality evidence suggests that the appropriate moment to perform tooth whitening in conventional orthodontic patients is after brackets removal with a waiting period of at least 30 days. There is not adequate evidence to support tooth whitening during conventional orthodontic treatment.